The estimated global prevalence of hepatitis C (HCV) infection is approximately 3% (170 million individuals). In Canada there are an estimated 240,000 people infected with HCV. The current study addresses the hypothesis that neurocognitive and neurochemical abnormalities may occur in individuals with HCV-infection who do not have liver cirrhosis or vasculitic neuropathy, and this may result from a direct effect of HCV on the Central Nervous System (CNS). The purpose of this study is to assess whether infection with the Hepatitis-C virus is associated with changes in thinking skills and brain chemistry, in patients who do not have liver cirrhosis. In addition, we are examining whether such changes in thinking skills and brain chemistry are reversed by antiviral treatment. We are also studying whether factors such as fatigue and depression have an effect on thinking skills in people with Hepatitis-C. In order to take into account the impact of having viral hepatitis, we will be comparing the results of the Hepatitis-C group to the results of a group of patients with Hepatitis-B, and to a group of individuals who do not have Hepatitis.

non-cirrhotic as determined by recent liver biopsy (<2 years prior to assessment)

HCV subjects: positive for HCV RNA, negative for HBV and HIV

HBV subjects: positive for HBV RNA and negative for HCV and HIV

Exclusion Criteria:

presence of any of the following medical conditions:

Thyroid dysfunction, or other endocrine disorder

Major psychiatric disease, especially major depression and bipolar disorder

Vitamin B12 or folate deficiency

Unstable cardiovascular disease (especially atrial fibrillation)

Unstable diabetes

Haemophilia (depending on frequency of medication usage)

The presence of other viral infections (HIV; syphilis)

Use of pharmaceuticals known to affect cognitive function

Current alcohol use greater than 2 units per day, or prior history of alcoholism

Use of illicit drugs within 2 years, or prior prolonged history

History of intravenous drug use within the past 5 years

History of any of the following neurological conditions: head injury with loss of consciousness greater than 30min., history of stroke, dementia, seizure disorder,recent substance abuse disorder (within 2 years), learning disability

Postmenopausal and perimenopausal female participants, unless hormone replacement therapy has been administered consistently for 2 years (on the basis that they may have concentration and memory dysfunction related to cholinergic deficits)

Contacts and Locations

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To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00188201